Generally, as a recording device which performs a recording process on a recording sheet as a recording medium, there is known a recording device which transports a recording sheet placed on an endless transport belt in a predetermined transport direction and attaches ink to the recording sheet so as to record an image thereon during a transport operation thereof. After the recording sheet subjected to such a recording process is further transported to a downstream side in the transport direction, a drying process is carried out so as to compulsorily dry the ink attached thereto during the recording process.
Incidentally, a restraint device for restraining the recording sheet to the transport belt is provided on the opposite side of a transport surface of the transport belt having the recording sheet placed thereon. The restraint device includes a platen as a support member capable of supporting the recording sheet via the transport belt. The platen is provided with a plurality of suction holes opened to the support surface (that is, a surface facing the transport belt). In addition, inside the platen, a plurality of negative pressure chambers (called as “suction chambers”) is defined in the transport direction, and the negative pressure chambers communicate with the outside via a plurality of suction holes. Further, the transport belt is provided with a plurality of communication holes provided so as to correspond to the plurality of suction holes provided in the platen.
In addition, the restraint device is provided with a pressure adjusting section capable of individually adjusting the negative pressure inside each of the negative pressure chambers. Then, in the case where the recording sheet is transported by the transport belt, the pressure adjusting section is driven so as to generate a negative pressure inside the negative pressure chamber located at the same position as that of the transported recording sheet in the transport direction. When the negative pressure is generated inside the negative pressure chambers by the driving operation of the pressure adjusting section, the negative pressure inside the negative pressure chambers is applied to the recording sheet disposed on the transport belt via the suction holes of the platen and the communication holes of the transport belt. Then, the negative pressure inside the negative pressure chamber serves as a restraining force which pushes downward the recording sheet against the transport belt. As a result, the recording sheet is restrained to the surface of the transport belt in the uniform surface state (for example, see Patent Document 1).
As an example, an effect when the restraint device is disposed on the downstream side of a recording member, used for attaching ink to the recording sheet, in the transport direction will be described. In the case where a recording process is performed on the recording sheet by means of the ink, a wood fiber (mainly including cellulose) as a main component of the recording sheet absorbs moisture of the ink to cause the swelling. As a result, the recording sheet absorbing the moisture of the ink may be deformed in an expanding manner by the swelled wood fibers pushing each other. That is, wrinkles may be formed in the recording sheet. When the restraining force, applied to the support surface, is applied to the recording sheet having the wrinkles formed therein, the recording sheet is restrained in a flat surface state, and the ink is naturally dried to be evaporated, thereby suppressing the wrinkles from being fixed to the recording sheet.
Patent Document 1 JP-A-H05-107969